Reduction gear



Aug. 1s, 1936. L SHORT 2,051,498

REDUCTION GEAR Filed May 29, 1935 Fla. Ei.

- INVENTOR IRA SHORT.

a, Q73 Wc-vv;

ATTORNEY Patented Aug. 18, 1936 UNITED STATES PATENT OFFICE REDUCTIONGEAR Sylvania Application May 29, 1935, Serial No. 24,047

3 Claims.

My invention relates to gears, more particularly of the marine reductiontype, and it has for an object to provide a relatively strong and lightdriven gear.

The driven gear of a marine reduction gear is ordinarily comprised by apair of spaced rims supported from a spindle. Heretofore, the supportingmeans has been commonly constituted by a cast structure. In my PatentNo. 1,874,713, granted August 30, 1932, there is disclosed and claimed aform of fabricated center structure serving the purposes of the usualcast structure. In accordance with my present invention, I providefurther improvements for gear centers of the general type disclosed andclaimed in said patent, the fabricated center of the present inventionbeing comprisedentirely by plate elements and being arranged in suchmanner that a simpler design results. My improved gear center iscomprised by outermost radial webs and an intermediate web structure,the intermediate web structure including pairs of aligned conical webelements arranged to constitute intersecting conical webs having theirouter edges joined internally of the gear rims and having their inneredges joined externally to the spindle.

A further object of my invention is to provide a gear having afabricated center, the center including intersecting conical webs joinedto the rims and to the spindle so as to provide a strong and relativelylight unitary gear structure.

A further object of my invention is to provide a fabricated center for agear and including outermost webs and an intermediate web structure, theintermediate web structure being comprised by intersecting conical websjoined to the rims and to the spindle of the gear.

A further object of my invention is to provide. a unitary gear structurecomprising a pair of spaced toothed rims and a spindle with a fabricatedcenter autogenously connected thereto,.

the center having its component parts so arranged that the rims arestrongly held in their positions against deection in all directionswhile at the same time preserving a very light structure.

These and other objects are effected by my invention, as will beapparent from the following description and claims taken in connectionwith the accompanying drawing, forming a part of this application, inwhich:

Fig` 1 is a View, partly in section and partly in elevation, and showingmy improved gear;

Fig. 2 is a detail View showing the weld connection of the basal ends ofthe inner conical web elements; Fig. 3 is a view showing the juxtaposedapical ends of the outer conical web elements encompassing thejuxtaposed basal ends of the inner conical web elements;

Fig. 4 is a View similar to Fig. 3, but showing the final annulus ofweld metal for joining the juxtaposed ends of the inner and outerconical web elements together; and,

Fig. 5 is a. modied form of construction for forming the intermediateweb structure.

Referring now to the drawing more in detail, in Fig. l, I show a spindleI 8 having a pair of axially spaced rims I I and IIa, provided withhelical teeth I Ibl and I Ic, respectively, which are inclined inopposite directions, and a fabricated center structure includingouter-most steel plate Webs I2 and IZa and an intermediate steel plateweb structure, at I3.

The outermost webs I2 and I2a are comprised by plate elements shaped tofit internally of the gear rims and externally of the spindle, thespindle preferably having annular enlargements providing seats I4 and I5for the inner edges of the webs. The outer edges of the plates arepreferably connected internally of the rims by means 20 of welds I6w andexternally of the seats I4 and I5 by means of welds I'Iw.

The intermediate web structure is comprised by inner conical webelements I8 and I8a and outer conical web elements I9 and ISa. Theapical ends 20 and 20a of the inner conical web elements I8 and I8arespectively, encompass the spindle, the latter preferably having a seat2| for the apical end 28 and the apical end 20a preferably encompassingthe seat I5. As shown, the apical ends 2D and 20a are connected to thespindle by means of welds 22u;i and 23W. The basal ends 24 and 24a ofthe inner conical web elements I8 and I8a are juxtaposed. The outerconical web elements I9 and I9a have their apical ends 25 and 25ajuxtaposed and encompassing the juxtaposed basal ends 24 and 24a, andthe basal ends of the outer conical web elements are joined internallyof the rims II and IIa by means of weld connections 26m. The juxtaposedbasal ends 24 and 24a and the apical ends 25 and 25a of the inner andouter conical web elements are connected together by an annularcomposite weld structure, at 21, the weld structure being comprised byan inner annular weld 28w joining the basal ends of the inner conicalweb elements I8 and Ia and by an outer annular weld 29w which is joinedboth to the weld 28w and to the juxtaposed apical ends 25 and 25a of theconical web elements I9 and ISa.

Thus, it will be seen that the inner conical web elements I8 and I8a arealigned, respectively, with the outer conical web elements I9a and I9 soas to constitute an intermediate web structure comprised by intersectingconical webs, the conical webs intersecting approximately at rightangles and being joined to the spindle adjacent to the radial webjunctions and being joined to the gear rims internally of the latter, toafford effective cross bracing of the gear.

In fabricating the gear, after the radial lweb I2 is placed on thespindle and Welded thereto, then theV inner conical web elements I8 andI8a are placed in position, the apical ends and 20a being Welded to thespindle and the ends being connected by the weld 28m. The weld 28m isnished to provide a cylindrical surface 28s so as to permit the readypositioning of the outer conical web elements I9 and ld, so that'thejuxtaposed ends 4and 25d Will encompass the juxtaposed not only joiningthe juxtaposed ends 25 and 25a,

but also being joined to the weld 28w, whereby the juxtaposed ends ofthe inner conical web elements and of the outer conical web elem-entsIare joined together by the annularvmetallic Weld structure, at 21.Next, the radial web I2a is placed on the spindle and connected theretoby means of the weld I'Iw.

The outer radialV edges of the outermost radial webs I2 and IZaand theintermediate web structure, at I3, are machined soV as Yto properly ntWithin thegear rims. The gear rims are then placed inv position `and thewelds at IIw and 26m are then made. plates I2 and I'2a are provided withopenings v3i! and 3Bato aiord internal access. Also, the conical webelement Ita is shown as provided with ,an opening 3l to afford accessfor internal weldmg. Y Y

As shown in Fig. 1the coupling Illa, for connecting the gear spindle totheV propeller shaft IUb is disposed at the left hand side, with theresult that the torque is transmitted entirely by the radial webs I2 andI2a and by the cone I8, the

cone I 8a serving very largely as a brace or stiiiren-Y ing member, inconsequence of which the opening 3|V may be provided in the cone I8aWithout impairing its strength for its operative purposes.

In Fig. 5, I show a modified form wherein, instead of a composite coneI8, I9a joining the rim IIa andthe spindle at a point adjacent to theradial web I2, as shown in Fig. l, a single cone I 8b isV employed, thecones'IBa and I9 being Welded thereto, as shown at lw'and |9171). An4advantage for this form is that the cone transmitting torque iscomprised by a single piece of metal. Y From the foregoing, it will beapparent that I have devised a reduction gear having a gear center whichis entirely fabricated vand which is joined to the rims and to thespindle so as to constitute a single autogenously connected structure,Not only may material of high and dependable quality be Vused,'butrthematerial may be so disposed as to be very stiff and strong. Stiiinessandl Y strength are vvaided Very largely by the intermediate webstructure, particularly because the latter is comprisedby conical webelements, a conical web being relatively stii inrall directions. Theintersecting conical Webs cross-brace the gear Y rims in such a mannerthat deflection of the gear center is strongly resisted in alldirections.

Since-V the crossed conical webs are each overlapped `by-bothr gearrims, not only is the arrangement compact, but is inherentlystrong,rstii and light and adequate compressive and tension strength isafforded bythe cross-bracing to prevent lateral deflection of the rimsWhile I have shown my invention in two forms, it Will be obvious tothose skilled in the art that it is not so limited, but is susceptibleof various changes and modifications Without departing To facilitatewelding, the radial from the spirit thereof, and I desire,therefore,that only such limitations shall be placed thereupon as areimposed by the prior' art or as are specifically set forth in theappended claims.

What I claim is:

l. In a gear, a pairrof spaced rims having opposed helical teeth, aspindle, means for supporting the rims from the spindle including steelplate outer webs and an intermediate fabricated web structure, the outerWebs having their outer edges joined circumferentially to and internallyof the gear rims and having their inner radial edges joinedcircumferentially to and externally of the spindle, and saidintermediate web structure including steel plate conical Webs connectedcirf' cumferentially to the rims and to` the spindle, said conical websintersecting'and joined together approximately at right angles to defineinner coni# cal elements joined to the spindle and outer conicalelements joined to the rims and the inner and outer conical elements ofVeach conical web being alined.- l'

2. In a gear, a pair of spacedV rims having opposed helical teeth; aspindle; and means for sup- L having their basal ends Weldedinternallyof the` rims and having juxtaposed apical ends encompassingthe juxtaposed basal ends of the inner conical Web elements, and meansfor joining together said juxtaposed basal and apical ends of the innerand outer conical web elements, respectively, so that the inner andouter conical web elements are aligned to provide conical webshav-` ingtheir inner ends joined to'the spindle and their outer ends joined tothe rims and which intersect approximately at right angles to provideeiective cross bracing of the gear.

3. In a gear, a pair of rims having opposed helical teeth; a spindle;and means for supporting the rims from the spindle and comprisingoutermost steel plate Webs and an intermediate fabri-` cated steel plateweb structure; said outermost f webs being radially disposed and havingtheir outer circumferential edges Welded to the rims internally of thelatter and having their inner circumferentialedges welded to the spindleexternally of the latter and said intermediate web structure includinginner conical web elements having their apical ends encompassing andwelded to the spindle and adjacent to the connections rims and to thespindle and which intersect. ap-

proximat'ely at right angles and are joined together to afford effectivecross-bracing vof 'the gear.

IRA SHORT.

